
package vlccontrol;

import java.beans.PropertyChangeSupport;
import java.io.*;
import java.io.IOException;
import java.nio.CharBuffer;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.commons.net.telnet.*;
import org.apache.commons.net.telnet.TelnetClient;

/**
 *  Exposes control of VLC media player (videolan.org) from java. VLC must be set up to open a telnet control on localhost:4444.
 * <p>
 * For VLC 1.1.5, use the following setup to expose the remote control (rc) interrface for telnet control:
 * <p>
 * This setting is in VLC Tools/Preferences/Show settings (All)/Interface/Main interfaces. Select the "Remote Control Interface" and replace "oldrc" with "rc" in the text field.
 * In VLC Tools/Preferences/Show settings (All)/Interface/Main interfaces/RC/TCP command input, put the string "localhost:4444" in the text field.
 *
 * @author Tobi
 */
public class VLCControl extends TelnetClient implements Runnable, TelnetNotificationHandler {

    /** VLC should be started with as "vlc --rc-host=localhost:4444" */
    public static final int VLC_PORT = 4444;
    static final Logger log = Logger.getLogger("VLCControl");
    private CharBuffer cbuf = CharBuffer.allocate(1024);
    private static VLCControl staticInstance = null; // used to communicate among instances the active client
    private PropertyChangeSupport support=new PropertyChangeSupport(this);  // listeners get informed by output from VLC strings

    public VLCControl() {
    }

    @Override
    public void disconnect() throws IOException {
        sendCommand("quit");
        super.disconnect();
    }

    public void connect(String password) throws IOException {
        staticInstance = this; // used by reader to get input stream
        try {
            staticInstance.connect("localhost", VLC_PORT);
            Thread thread = new Thread(new VLCControl()); // starts the thread to get the text sent back from VLC
            thread.start();
            staticInstance.registerNotifHandler(this); // notifications call back to logger

            sendCommand(password);
            Runtime.getRuntime().addShutdownHook(new Thread() { // shutdown hook here makes sure to disconnect cleanly, as long as we are not terminated

                @Override
                public void run() {
                    try {
                        if (isConnected()) {
                            disconnect();
                        }
                    } catch (IOException ex) {
                        log.warning(ex.toString());
                    }
                }
            });
        } catch (IOException e) {
            log.warning("couldn't connect to VLC - you may need to start VLC with command line \"vlc --rc-host=localhost:4444\"");
            throw new IOException(e);
        }
    }



    /** Sends a string command.  Commands do not need to be terminated with a newline.
     <p>
     <pre>
     +----[ Remote control commands ]
     | add XYZ  . . . . . . . . . . . . . . . . . . . . add XYZ to playlist
     | enqueue XYZ  . . . . . . . . . . . . . . . . . queue XYZ to playlist
     | playlist . . . . . . . . . . . . . .show items currently in playlist
     | search [string]  . .  search for items in playlist (or reset search)
     | sort key . . . . . . . . . . . . . . . . . . . . . sort the playlist
     | sd [sd]  . . . . . . . . . . . . . show services discovery or toggle
     | play . . . . . . . . . . . . . . . . . . . . . . . . . . play stream
     | stop . . . . . . . . . . . . . . . . . . . . . . . . . . stop stream
     | next . . . . . . . . . . . . . . . . . . . . . .  next playlist item
     | prev . . . . . . . . . . . . . . . . . . . .  previous playlist item
     | goto . . . . . . . . . . . . . . . . . . . . . .  goto item at index
     | repeat [on|off]  . . . . . . . . . . . . . .  toggle playlist repeat
     | loop [on|off]  . . . . . . . . . . . . . . . .  toggle playlist loop
     | random [on|off]  . . . . . . . . . . . . . .  toggle playlist random
     | clear  . . . . . . . . . . . . . . . . . . . . . .clear the playlist
     | status . . . . . . . . . . . . . . . . . . . current playlist status
     | title [X]  . . . . . . . . . . . . . . set/get title in current item
     | title_n  . . . . . . . . . . . . . . . .  next title in current item
     | title_p  . . . . . . . . . . . . . .  previous title in current item
     | chapter [X]  . . . . . . . . . . . . set/get chapter in current item
     | chapter_n  . . . . . . . . . . . . . .  next chapter in current item
     | chapter_p  . . . . . . . . . . . .  previous chapter in current item
     |
     | seek X . . . . . . . . . . . seek in seconds, for instance `seek 12'
     | pause  . . . . . . . . . . . . . . . . . . . . . . . .  toggle pause
     | fastforward  . . . . . . . . . . . . . . . . . . set to maximum rate
     | rewind . . . . . . . . . . . . . . . . . . . . . set to minimum rate
     | faster . . . . . . . . . . . . . . . . . .  faster playing of stream
     | slower . . . . . . . . . . . . . . . . . .  slower playing of stream
     | normal . . . . . . . . . . . . . . . . . .  normal playing of stream
     | rate [playback rate] . . . . . . . . . .  set playback rate to value
     | frame  . . . . . . . . . . . . . . . . . . . . . play frame by frame
     | fullscreen, f, F [on|off]  . . . . . . . . . . . . toggle fullscreen
     | info . . . . . . . . . . . . . .information about the current stream
     | stats  . . . . . . . . . . . . . . . .  show statistical information
     | get_time . . . . . . . . . .seconds elapsed since stream's beginning
     | is_playing . . . . . . . . . . . .  1 if a stream plays, 0 otherwise
     | get_title  . . . . . . . . . . . . . the title of the current stream
     | get_length . . . . . . . . . . . .  the length of the current stream
     |
     | volume [X] . . . . . . . . . . . . . . . . . .  set/get audio volume
     | volup [X]  . . . . . . . . . . . . . . . .raise audio volume X steps
     | voldown [X]  . . . . . . . . . . . . . .  lower audio volume X steps
     | adev [X] . . . . . . . . . . . . . . . . . . . .set/get audio device
     | achan [X]  . . . . . . . . . . . . . . . . . .set/get audio channels
     | atrack [X] . . . . . . . . . . . . . . . . . . . set/get audio track
     | vtrack [X] . . . . . . . . . . . . . . . . . . . set/get video track
     | vratio [X] . . . . . . . . . . . . . . . .set/get video aspect ratio
     | vcrop, crop [X]  . . . . . . . . . . . . . . . .  set/get video crop
     | vzoom, zoom [X]  . . . . . . . . . . . . . . . .  set/get video zoom
     | snapshot . . . . . . . . . . . . . . . . . . . . take video snapshot
     | strack [X] . . . . . . . . . . . . . . . . . set/get subtitles track
     | hotkey, key [hotkey name]  . . . . . . . . . . simulate hotkey press
     | menu [on|off|up|down|left|right|select]  . . . . . . . . . .use menu
     |
     | set [var [value]]  . . . . . . . . . . . . . . . . . set/get env var
     | save_env . . . . . . . . . . . .  save env vars (for future clients)
     | alias [cmd]  . . . . . . . . . . . . . . . . set/get command aliases
     | description  . . . . . . . . . . . . . . . . . .describe this xtreamclient.module
     | license  . . . . . . . . . . . . . . . . print VLC's license message
     | help, ? [pattern]  . . . . . . . . . . . . . . . . . .a help message
     | longhelp [pattern] . . . . . . . . . . . . . . a longer help message
     | logout . . . . . . . . . . . . . .  exit (if in a socket connection)
     | quit . . . . . . . .  quit VLC (or logout if in a socket connection)
     | shutdown . . . . . . . . . . . . . . . . . . . . . . . .shutdown VLC
     +----[ end of help ]
     </pre>

     */
    public String sendCommand(String s) throws IOException {
        if (!isConnected()) {
            //connect();
            throw new IOException("Not connected");
        }
        if (s == null) {
            return null;
        }
        if (!s.endsWith("\n")) {
            s = s + "\n";
        }
        getOutputStream().write(s.getBytes());
        getOutputStream().flush();
        return s;
    }

    public static String PAUSE="pause", PLAY="play", STOP="stop", NEXT="next", PREV="prev", VOLUP="volup 1", VOLDOWN = "voldown 1";
    public static final String CLIENT_MESSAGE="ClientMessage";
    /***
     * Reader thread.
     * Reads lines from the TelnetClient and echoes them
     * on the logger.
     * PropertyChangeListeners are called with CLIENT_MESSAGE and String sent from VLC.
     ***/
    @Override
    public void run() {
        InputStream instr = staticInstance.getInputStream();

        byte[] buff = new byte[1024];
        int ret_read = 0;

        try {
            do {
                ret_read = instr.read(buff);
                if (ret_read > 0) {
                    String s=new String(buff, 0, ret_read);
                    log.info(s);
                    staticInstance.getSupport().firePropertyChange(CLIENT_MESSAGE, null, s); // listener on static instance that actually is connected gets the message
                }
            } while (ret_read >= 0);
        } catch (Exception e) {
            log.log(Level.WARNING, "Reader ending - Exception while reading socket:{0}", e.getMessage());
        }
    }

    /***
     * Callback method called when TelnetClient receives an option
     * negotiation command.
     * <p>
     * @param negotiation_code - type of negotiation command received
     * (RECEIVED_DO, RECEIVED_DONT, RECEIVED_WILL, RECEIVED_WONT)
     * <p>
     * @param option_code - code of the option negotiated
     * <p>
     ***/
    @Override
    public void receivedNegotiation(int negotiation_code, int option_code) {
        String command = null;
        if (negotiation_code == TelnetNotificationHandler.RECEIVED_DO) {
            command = "DO";
        } else if (negotiation_code == TelnetNotificationHandler.RECEIVED_DONT) {
            command = "DONT";
        } else if (negotiation_code == TelnetNotificationHandler.RECEIVED_WILL) {
            command = "WILL";
        } else if (negotiation_code == TelnetNotificationHandler.RECEIVED_WONT) {
            command = "WONT";
        }
        log.log(Level.INFO, "Received {0} for option code {1}", new Object[]{command, option_code});
    }

    /**
     * @return the support. Listeners can get the stuff sent back from VLC with CLIENT_MESSAGE events.
     */
    public PropertyChangeSupport getSupport() {
        return support;
    }
}